Prevalence, time trends, and correlates of major depressive episode and other psychiatric conditions among young people amid major social unrest and COVID-19 in Hong Kong: a representative epidemiological study from 2019 to 2022

Background: Hong Kong is among the many populations that has experienced the combined impacts of social unrest and the COVID-19 pandemic. Despite concerns about further deteriorations in youth mental health globally, few epidemiological studies have been conducted to examine the prevalence and correlates of major depressive episode (MDE) and other major psychiatric disorders across periods of population-level changes using diagnostic interviews. Methods: We conducted a territory-wide household-based epidemiological study from 2019 to 2022 targeting young people aged 15–24 years. MDE, generalised anxiety disorder (GAD), panic disorder (PD), and bipolar disorder (BD) were assessed using the Composite International Diagnostic Interview–Screening Scales in 3340 young people. Psychotic disorders were assessed by experienced psychiatrists according to the DSM. Help-seeking patterns were also explored. Findings: 16.6% had any mental disorder (13.7% 12-month MDE, 2.3% BD, 2.1% GAD, 1.0% PD, 0.6% psychotic disorder). The prevalence of MDE increased from 13.2% during period 1 (May 2019–June 2020) to 18.1% during period 2 (July–December 2020), followed by 14.0% during period 3 (January–June 2021) and 13.2% during period 4 (July 2021–June 2022). Different stressors uniquely contributed to MDE across periods: social unrest-related stressors during period 1, COVID-19 stressors during period 2, and personal stressors during periods 3–4. Lower resilience, loneliness, frequent nightmares, and childhood adversity were consistently associated with MDE. Compared to other conditions, those with MDE showed the lowest service utilisation rate (16.7%). Perceiving services to “cost too much” and “talked to friends or relatives instead” were among the major reasons for not seeking help. MDE was also significantly associated with poorer functioning and health-related quality of life. Interpretation: MDE can be sensitive to population-level changes, although its persistently elevated prevalence across the study period is of concern. Efforts to mitigate their impacts on youth mental health alongside personal risk factors are needed. Further work is required to increase the availability and acceptability of youth-targeted mental health services. Funding: Food and Health Bureau (HKSAR Government)

No Reliable Association between Runs of Homozygosity and Schizophrenia in a Well-Powered Replication Study

It is well known that inbreeding increases the risk of recessive monogenic diseases, but it is less certain whether it contributes to the etiology of complex diseases such as schizophrenia. One way to estimate the effects of inbreeding is to examine the association between disease diagnosis and genome-wide autozygosity estimated using runs of homozygosity (ROH) in genome-wide single nucleotide polymorphism arrays. Using data for schizophrenia from the Psychiatric Genomics Consortium (n = 21,868), Keller et al. (2012) estimated that the odds of developing schizophrenia increased by approximately 17% for every additional percent of the genome that is autozygous (β = 16.1, CI(β) = [6.93, 25.7], Z = 3.44, p = 0.0006). Here we describe replication results from 22 independent schizophrenia case-control datasets from the Psychiatric Genomics Consortium (n = 39,830). Using the same ROH calling thresholds and procedures as Keller et al. (2012), we were unable to replicate the significant association between ROH burden and schizophrenia in the independent PGC phase II data, although the effect was in the predicted direction, and the combined (original + replication) dataset yielded an attenuated but significant relationship between Froh and schizophrenia (β = 4.86,CI(β) = [0.90,8.83],Z = 2.40,p = 0.02). Since Keller et al. (2012), several studies reported inconsistent association of ROH burden with complex traits, particularly in case-control data. These conflicting results might suggest that the effects of autozygosity are confounded by various factors, such as socioeconomic status, education, urbanicity, and religiosity, which may be associated with both real inbreeding and the outcome measures of interest

Female chromosome X mosaicism is age-related and preferentially affects the inactivated X chromosome

To investigate large structural clonal mosaicism of chromosome X, we analysed the SNP microarray intensity data of 38,303 women from cancer genome-wide association studies (20,878 cases and 17,425 controls) and detected 124 mosaic X events42Mb in 97 (0.25%) women. Here we show rates for X-chromosome mosaicism are four times higher than mean autosomal rates; X mosaic events more often include the entire chromosome and participants with X events more likely harbour autosomal mosaic events. X mosaicism frequency increases with age (0.11% in 50-year olds; 0.45% in 75-year olds), as reported for Y and autosomes. Methylation array analyses of 33 women with X mosaicism indicate events preferentially involve the inactive X chromosome. Our results provide further evidence that the sex chromosomes undergo mosaic events more frequently than autosomes, which could have implications for understanding the underlying mechanisms of mosaic events and their possible contribution to risk for chronic diseases

Estimation of Genetic Correlation via Linkage Disequilibrium Score Regression and Genomic Restricted Maximum Likelihood

J. Lönnqvist on työryhmän Psychiat Genomics Consortium jäsen.Genetic correlation is a key population parameter that describes the shared genetic architecture of complex traits and diseases. It can be estimated by current state-of-art methods, i.e., linkage disequilibrium score regression (LDSC) and genomic restricted maximum likelihood (GREML). The massively reduced computing burden of LDSC compared to GREML makes it an attractive tool, although the accuracy (i.e., magnitude of standard errors) of LDSC estimates has not been thoroughly studied. In simulation, we show that the accuracy of GREML is generally higher than that of LDSC. When there is genetic heterogeneity between the actual sample and reference data from which LD scores are estimated, the accuracy of LDSC decreases further. In real data analyses estimating the genetic correlation between schizophrenia (SCZ) and body mass index, we show that GREML estimates based on similar to 150,000 individuals give a higher accuracy than LDSC estimates based on similar to 400,000 individuals (from combinedmeta-data). A GREML genomic partitioning analysis reveals that the genetic correlation between SCZ and height is significantly negative for regulatory regions, which whole genome or LDSC approach has less power to detect. We conclude that LDSC estimates should be carefully interpreted as there can be uncertainty about homogeneity among combined meta-datasets. We suggest that any interesting findings from massive LDSC analysis for a large number of complex traits should be followed up, where possible, with more detailed analyses with GREML methods, even if sample sizes are lesser.Peer reviewe

Native diversity buffers against severity of non-native tree invasions

Determining the drivers of non-native plant invasions is critical for managing native ecosystems and limiting the spread of invasive species1,2. Tree invasions in particular have been relatively overlooked, even though they have the potential to transform ecosystems and economies3,4. Here, leveraging global tree databases5–7, we explore how the phylogenetic and functional diversity of native tree communities, human pressure and the environment influence the establishment of non-native tree species and the subsequent invasion severity. We find that anthropogenic factors are key to predicting whether a location is invaded, but that invasion severity is underpinned by native diversity, with higher diversity predicting lower invasion severity. Temperature and precipitation emerge as strong predictors of invasion strategy, with non-native species invading successfully when they are similar to the native community in cold or dry extremes. Yet, despite the influence of these ecological forces in determining invasion strategy, we find evidence that these patterns can be obscured by human activity, with lower ecological signal in areas with higher proximity to shipping ports. Our global perspective of non-native tree invasion highlights that human drivers influence non-native tree presence, and that native phylogenetic and functional diversity have a critical role in the establishment and spread of subsequent invasions

University students' attitudes towards mental patients and psychiatric treatment

Background: Public attitudes towards mental patients and psychiatric treatment are mostly unfavorable. Mental patients tend to conceal their illness or selectively disclose their treatment histories to someone they trust. Aims: To examine the university students' attitudes towards different information regarding a person labeled as mentally ill. Methods: We designed seven descriptions of a mentally ill person of varying past and current treatment histories and randomly assigned 308 university undergraduates to read one of the descriptions. Subjects rated their willingness to interact with the hypothetical case using a 19-item social distance scale. Results: Greater social distance was associated with non-medical field of study, no previous contact with the mentally ill and female gender. Subjects without previous contact with mentally ill individuals kept greater distance from a discharged mental patient receiving psychiatric care than a mental patient who did not require medications nor psychiatric follow-up. In contrast, respondents who had previous contact with the mentally ill were more willing to interact with a discharged mental patient receiving psychiatric care comparing with a person labeled as mentally ill alone and a mental patient who had never been admitted to hospital. Conclusions: Implications of our findings in clinical management and designing stigma-reducing programme are discussed.link_to_subscribed_fulltex

Real-world implementation of early intervention in psychosis: resources, funding models and evidence-based practice

link_to_subscribed_fulltex